Associate Software Engineer

You are given a string ‘str’, your task is to convert all the characters of the string into lowercase letters.

For example:

You are given, ‘str’ = ‘AbcdEfgh’, in this string if you convert all the characters into lowercase, the string will be ‘abcdefgg’. Hence it is the answer.

You are given the head node of a singly linked list 'head'. Your task is to modify the linked list in such a way that all the even valued nodes appear before the all odd valued node and order of nodes remain the same.

Example :-

The given singly linked list is  6 -> 5 -> 3 -> 4 -> 7 -> 1 -> 2 

The modified linked list should have all even values in starting and odd values in the end.

You are given a number 'N'. Your task is to find Nth prime number.

A prime number is a number greater than 1 that is not a product of two smaller natural numbers. Prime numbers have only two factors – 1 and the number itself.

Any number greater than 0 is a natural number i.e. natural numbers N = {1, 2, 3, 4,....}

For example:-

If you are asked to find the 7th prime number, it’ll be 17 because the first 7 prime numbers are 2, 3, 5, 7, 11, 13, 17.

Note: 1 is not a prime number.

Follow Up:

Try to solve the problem in O(N log log N) + O(N).

You are given a string ‘S’ of length ‘N’. You have to return all the characters in the string that are duplicated and their frequency.

Example:-

N = 5
S = ‘GEEK’

ANSWER:- The answer should be [(‘E’,2)] because ‘E’ is the only character that is duplicated and has frequency 2.